CVE & CISA-KEV CatalogNVD
CVE-2015-7855
MEDIUMEPSS 98th pctl6.5
CVSS v3
Description
The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (assertion failure) via a 6 or mode 7 packet containing a long data value.
CVSS v3 Vector
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Exploit Intelligence
31.07%probability of exploitation in 30 days
98thpercentile
Very high risk: more likely to be exploited than 98% of all known CVEs.
References
- http://support.ntp.org/bin/view/Main/NtpBug2922
- http://www.debian.org/security/2015/dsa-3388
- http://www.securityfocus.com/bid/77283
- http://www.securitytracker.com/id/1033951
- https://bugzilla.redhat.com/show_bug.cgi?id=1274264
- https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05270839
- https://security.gentoo.org/glsa/201607-15
- https://security.netapp.com/advisory/ntap-20171004-0001/
- https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11
- https://www.exploit-db.com/exploits/40840/
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Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-13.